On the modeling of MMC for use in large scale dynamic simulations

This paper focuses on simplified models of the
Modular Multilevel Converter suitable for large-scale dynamic
studies, in particular simulations under the phasor approximation.
Compared to the existing literature, this paper does not a
priori adopt the modeling approach followed for the original twolevel
or three-level Voltage Source Converter. On the contrary,
a model is derived following a physical analysis that preserves
its average internal dynamic behavior. An equivalent control
structure is proposed and various alternatives are highlighted.
The proposed model with its controllers has been implemented
in a phasor simulation software and its response has been
validated against a detailed Electromagnetic Transient model.
Finally, an illustrative example is presented with the application
of the proposed model on a large grid consisting of AC areas
interconnected with a multi-terminal DC grid.